* The films that displayed the smallest percent change in mass were PVOH(22K)+0.8wt%GA+100%CECMT (exchanged with CuSO<sub>4</sub>) and PVOH(22K)+1mLGA+1mLPP.

+

* The films that displayed the largest percent change in mass were PVOH(22K)+0.5mLGA+100%CECMT, PVOH(22K)+0.5mLGA+NaMT, and PVOH(22K)+0.5mLGA+1mLPP.

+

* Effect of ion exchange?

+

* It appears that adding 0.5 mL of glutaraldehyde to the films does not induce sufficient crosslinking to prevent swelling. However, 1 mL of glutaraldehyde seemed to reduce the degree to which the films swelled.

+

* Overall, most films displayed about a 100% increase in mass. In other words, their mass approximately doubled due to swelling.

Current revision

Objectives

Soak PVOH (MW 22000) in HPLC grade H2O to determine change in mass due to swelling.

Soak PVOH (MW 22000), 1 mL glutaraldehyde, 1 mL porphyrin in 2 wt% H2SO4 until the film turns green. Then soak the film in salt solution and take UV-vis of the film.

PVOH (MW 22000) Film Swelling

Change in mass of PVOH (MW 22000) films after soaking in 10 mL HPLC grade H2O for three days.

Crosslinked Film

Date Prepared

Initial Mass [g]

Final Mass [g]

ΔMass [g]

% Change []

PVOH(22K),0.5mLGA,NaMT

11/2/2012

0.0241

0.0871

0.063

261.4107884

PVOH(22K),0.5mLGA,1mLPP

10/26/2012

0.0398

0.1132

0.0734

184.4221106

PVOH(22k),0.5mLGA,0.99mLPP

10/19/2012

0.0312

0.0872

0.056

179.4871795

PVOH(22k),8.24µLGA,50%CECMT,CuSO4exch.

10/17/2012

0.0113

0.0242

0.0129

114.159292

PVOH(22k),8.24µLGA,100%CECMT,CuSO4exch.

10/17/2012

0.0048

0.0095

0.0047

97.91666667

PVOH(22k),1mLGA,50%CECMT

10/4/2012

0.0138

0.0294

0.0156

113.0434783

PVOH(22k),1mLGA,100%CECMT

10/4/2012

0.0144

0.0307

0.0163

113.1944444

PVOH(22k),1mLGA,1mLPP,less colored

10/24/2012

0.014

0.0241

0.0101

72.14285714

PVOH(22k),1mLGA,0.1gNaMT,CuSO4exch.

10/17/2012

0.0102

0.0222

0.012

117.6470588

PVOH(22k),0.5mLGA,1mLPP

10/24/2012

0.0279

0.0596

0.0317

113.6200717

PVOH(22k),1mLGA,1mLPP

---

0.0369

0.0687

0.0318

86.17886179

PVOH(22k),8.24µLGA,100%CECMT

---

0.0447

0.1038

0.0591

132.2147651

PVOH(22k),0.5mLGA,100%CECMT

10/19/2012

0.0115

0.0425

0.031

269.5652174

The films that displayed the smallest percent change in mass were PVOH(22K)+0.8wt%GA+100%CECMT (exchanged with CuSO4) and PVOH(22K)+1mLGA+1mLPP.

The films that displayed the largest percent change in mass were PVOH(22K)+0.5mLGA+100%CECMT, PVOH(22K)+0.5mLGA+NaMT, and PVOH(22K)+0.5mLGA+1mLPP.

Effect of ion exchange?

It appears that adding 0.5 mL of glutaraldehyde to the films does not induce sufficient crosslinking to prevent swelling. However, 1 mL of glutaraldehyde seemed to reduce the degree to which the films swelled.

Overall, most films displayed about a 100% increase in mass. In other words, their mass approximately doubled due to swelling.

Standardization of NaHCO3

Protocol

Weigh out 20 g of potassium hydrogen phthalate (KHP).

The mass was divided into thirds, and then dried in the oven at 90°C for 48 hours.

Each sample was divided in half again to give six samples of KHP total.

One sample was placed in a 100 mL beaker and 2 drops of bromothymol blue was added.

1 M NaHCO3 was poured into a titration buret and the initial volume was recorded.

The KHP was titrated with the NaHCO3 solution until the solution in the beaker turned blue and stopped fizzing.